We did the VOR 13L down to mins before they switched the runway. While we were waiting for a gate...over 2 hours...I saw an AA heavy (dont know whether it was a 767 or a A300) land on 4R and all the trucks surrounded it. I dont know what happened but it tied up the runway change for awhile. Departures were stopped at one point for about 45min. It was not a good day to be in JFK. We made over 4 hours though.